Satellites for communications and broadcast services can operate in orbit to communicate to a ground device by generating a forward user downlink signal for reception by the ground device. In return, the ground device can transmit back a return user uplink signal to the satellite. Often, the forward user downlink signal is based on the transmission of several signals from several antennas configured as a phased array antenna. If the phases and amplitudes of the signals are relatively similar, then the signals can be coherently combined. This results in a higher-powered forward user downlink signal as received by the ground device.
The phased array antenna should be calibrated to increase the power of the forward user downlink signals, and therefore, increase the performance of the communication from the satellite to ground devices. Thus, an improved system for calibrating channels of a satellite is desired.